Systems for optical analysis of a test liquid during chromatography generally include a light source, a diffraction grating, filter, or other means for selecting a wavelength, a flow cell to allow interrogation of the test liquid during the chromatographic analysis with the selected wavelength, and a detector. The flow cell must be constructed from materials that are resistant to the solutions encountered in liquid chromatography. To achieve high sensitivity, the flow cell must have a small volume to prevent peak dispersion and a long pathlength. These and other considerations of flow cell design require tradeoffs between sensitivity, throughput, peak resolution, and manufacturability.